I want to show a containment reference as link. My model has the following structure (Model contains A, A contains B):

Model
|- A
|- B
-

In Galileo, I can have a top node reference for B and leave it's containmentFeature empty. The containment reference from A to B is visualized as a link. It's possible to edit the containment hierarchy by drawing links and also to initialize a new diagram, which displays the containment hierarchy as links.
In Helios, I get a compilation error in a "CanonicalUpdatePolicy" when I leave a containmentFeature empty.

Any ideas how to overcome this? Isn't this use case supported anymore?